Although I completely understand people think I should sit them down and tell them not to, I think I have just bored my family enough with talk of PTSD that I don't want to mention it anymore unless I have to.
if people aren't willing to listen to reason, or don't really listen to a word that you are saying because you are being "over-sensitive"
I don't want to make you feel harassed on this point, but did want to say something about it. When I started getting PTSD symptoms I'd been in my then job a long time and there was a lot of joking and messing around in the office, including giving each other frights. Obviously, this became awful for me, but because I was so jumpy the others thought it was funnier and did it more. I had to tell them very straightforwardly, and repeatedly, "Seriously, this is really upsetting me" - not saying it in a lighthearted way, or accusingly, just telling them. It took a while and they clearly thought I was spoiling the atmosphere but they did finally stop. In the end, the atmosphere wasn't spoilt, we still got on and joked around, just not making each other jump any more.
I'm sure your family love you as much as you love them and simply don't understand that this is actually distressing for you. Can you show them something, maybe printed off the internet, about how the startle response is a serious symptom of PTSD and explain in a direct way that its no fun for you at all?
With regard to coping better after you've been startled, I'd suggest trying two things and seeing if they help:
Practising calming yourself down afterwards, ie rehearsing this, at times when you aren't startled. Pretend something has given you a fright (you don't need to do any pretend jumping, imagine it's immediately after), then practise doing the things that are calming for you. In my case, this was putting my hand on my tummy (soothing for me, and helped me measure my breathing), deep breaths, telling myself my name and where I was, getting my bottle of peppermint oil and smelling it etc. It's a bit like doing fire drills so that when the fire alarm does go off unexpectedly, the steps to take are automatic and you can do them more quickly.
Keep reminding yourself that there might be noises etc which are OK. When you arrive somewhere tell yourself that while you're there, there might be a knock on the door, or someone calling out, and whatever else there might be. Remind yourself of that as often as you can. If you can attach the thought to something you'll notice every now and then, like your watch, then every time you look at your watch you can remember it.
I think my tendency to dissociate made the startle response worse, because the noise or movement would be snapping me back out of a slight fog. If I'd had more general awareness and been tuned in to my surroundings, it wouldn't have been so unexpected. Planting the idea of possible noises etc into my mind in a reassuring way helped me expect them a bit more, and re-stabilise more quickly if something did make me jump.
I also agree with Abstract's suggestion of working on mindfulness and meditation (for me, guided relaxation was easier than meditation). Doing things like this, together with working on healing in therapy etc, does make the startle response go away.
